Improperly placed neighborhood traffic calming signs may be hazardous

Dear Street Smarts,
Q: A neighbor on Wesley Street in Capitola had one of those brightly colored plastic turtle signs asking drivers to slow down. It was placed a little farther out in the street than the parked cars. One day, I noticed the turtle was gone and, a few days later, replaced with a homemade wood stand, not brightly colored, with a paper sign stating 'DEAF CAT.' There are a number of cats that tend to go out in the street in our neighborhood. One of them is apparently deaf. I sympathize with the neighbor, who has small children and lives on a straight street that is a shortcut through the neighborhood. I raised my kids in the neighborhood myself and understand the desire to slow cars down and keep kids safe. My concern is that the sign isn’t brightly colored and seems to stick out a bit far into the street. Their house is a few doors away from Park Avenue, which is a bit busier. The placement of the sign pushes cars going toward Park to the left of their lane while cars turning left from Park might be cutting into that lane as well. It seems dangerous. Are there rules about the placement of the sign? I am worried that with the shorter days, the sign might not be very visible and cause an accident.
Thank you,
Chris Bowman, CapitolaA: "The placement of signs in the road right of way is controlled by city code and private signs are illegal," said Steve Jesberg, director of the city's public works department. "Unfortunately, with the proliferation of these new 'slow down signs' being sold, many people feel empowered to use them. We do not have the crew time to continually enforce these illegal signs and typically only take action if they are creating a traffic hazard. The signs tend to pop up and be taken down much faster than we can respond."
Jesberg encourages users of these signs to "keep them close to the curb or parked cars so they don’t create problems," he said. "There could be some liability for anyone placing a sign in the roadway if it were to cause injury or damage."